Mr Vincent, who was an expert witness in the Lockerbie bombing trial, said: “The data released thus far most likely points to a problem with hazardous materials.

“This scenario begins with the eruption of hazardous materials within the cargo hold – either improperly packaged or illegally shipped – or both.”

Mr Vincent believes a fire started in the cargo hold and gradually destroyed the plane’s communications systems.

He says toxic fumes would have quickly overwhelmed the passengers and cockpit.

Mr Vincent guesses that one of the pilots managed to put on an oxygen mask and tried to turn the plane back to Kuala Lumpur.

He puts the plane’s rapid ascent and descent down to the crew simply not being able to see properly until they manage to stabilise at 23,000 ft.

Mr Vincent added: “The airplane then continues flying until no fuel remains and crashes – most likely into the ocean as there has been no report of any Emergency Locater Transmitter (ELT) signal which can be received by satellite if the crash were on land.”

And Mr Vincent, who played a key role in negotiations after the hijackings of US planes during the 1980s, insists it is unlikely the aircraft was sabotaged.

He said: “There is no indication that either of the pilots was criminally involved in the disappearance of this aeroplane.

“Neither has Malaysia released any data indicating anything amiss in the security clearance of the passengers for this flight.

“The one question raised about the two passengers travelling on stolen passports has been cleared indicating that they were planning on illegally claiming refugee status in another country, probably Germany.

“I have yet to see anything released about the nature and content of the cargo carried in the cargo hold of MH370.

“Hazardous cargo can be legally carried on passenger aircraft. However, the amount and type of such hazardous materials are strictly controlled.”